A method for obtaining the reduction ratio of a continuous rolling mill unit that can reduce roll wear
Optimizing rolling rates using genetic or particle swarm algorithms minimizes frictional power consumption, reducing roll wear and enhancing production capacity by iteratively calculating rolling force, torque, and motor power in continuous rolling processes.
Patent Information
- Application Number
- CN202211350074.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-10-31
- Publication Date
- 2025-07-15
- Estimated Expiration
- 2042-10-31
AI Technical Summary
The prior art cannot preset the pressure rate of each stand of the continuous rolling mill in real time in real time during continuous rolling production, resulting in large amount of roll wear and lack of evaluation standards, which affects production stability and efficiency.
By establishing a continuous rolling mill group pressure ratio allocation model with the minimum roll joint friction work optimization target, optimization algorithms such as genetic algorithms or particle swarm algorithms are used to calculate the pressure ratio of each rack and obtain the optimal pressure ratio allocation, including repeated calculation of rolling capacity parameters to meet the optimization goals and constraints.
The online preset calculation of the pressure rate of continuous rolling mill units is realized, which reduces roll wear, reduces roll change frequency, increases the rolling production during the single roll period, and avoids the error caused by the manual experience table setting method.
Smart Images
Figure CN115672991B_ABST
Abstract
Description
Technical Field
[0001] This embodiment relates to the rolling field, and particularly to a method for obtaining the reduction rate of a continuous rolling mill unit that can reduce roll wear. Background Art
[0002] During the continuous rolling production process, the reduction rate distribution of each stand of the continuous rolling mill is one of the most important continuous rolling process parameters, which directly determines the stability and smooth progress of the production process and is also a basic parameter for controlling the thickness and shape of the rolled piece. The existing technology often uses the artificial experience table setting method to distribute the reduction rate of each stand of the continuous rolling mill. The establishment of this experience table requires a large amount of production practice data and operation experience in the early stage. When the product specification is changed, it takes a long time to re - establish the new table data, and it cannot perform real - time online pre - setting calculation of the reduction rate distribution according to the new product specification. In addition, there is no evaluation standard for the table data for comparison. For example, it is impossible to evaluate whether the roll wear is small, resulting in a large amount of roll wear in the given continuous rolling reduction rate distribution. Therefore, it is necessary to further develop a method for obtaining the reduction rate of a continuous rolling mill unit that can reduce roll wear.
[0003] Content of the Embodiment
[0004] In view of the above problems, this embodiment is proposed to provide a method for obtaining the reduction rate of a continuous rolling mill unit that can overcome the above problems or at least partially solve the above problems.
[0005] In order to solve the above technical problems, the embodiments of the present application disclose the following technical solutions:
[0006] A method for obtaining the reduction rate of a continuous rolling mill unit that can reduce roll wear, comprising:
[0007] S100. Input process parameters and continuous rolling mill equipment parameters;
[0008] S200. Establish an optimization target and constraint conditions for the minimum roll gap friction work;
[0009] S300. Use an optimization algorithm to initially set the reduction rates η1, η2... ηQ - 1 of the 1st stand to the (Q - 1)th stand; Q-1 ;
[0010] S400. Calculate the inlet thickness and outlet thickness of the rolled piece for each stand;
[0011] S500. Calculate the rolling force and energy parameters for each stand, where the rolling force and energy parameters for each stand include the rolling pressure, transmission torque, forward slip value, roll speed, and main motor power of each stand;
[0012] S600. Determine whether the minimum roll gap friction work optimization objective and the constraints are satisfied simultaneously: If not, adjust the reduction rate values of each stand by the optimization algorithm, and then transfer to S400 for recalculation. If satisfied, the calculation ends.
[0013] Furthermore, in S100, the process parameters include the incoming material thickness H (unit: mm), the finished product thickness h (unit: mm), the width B of the rolled piece s (unit: mm), the number of stands Q, and the rolled piece deformation resistance data. The continuous rolling mill equipment parameters include the working roll body diameter D wk (unit: mm), the working roll neck diameter D′ wk (unit: mm), the working roll body width B wk (unit: mm), the backup roll body diameter D bk (unit: mm), the backup roll neck diameter D′ bk (unit: mm), and the backup roll body width B bk (unit: mm), where the subscript k represents the stand number, and 1 ≤ k ≤ Q.
[0014] Furthermore, in S200, the objective function of the minimum roll gap friction work optimization objective is:
[0015]
[0016] In the formula, n k is the number of discrete segments of the roll gap of the k -th stand, t k (i) is the friction stress of the i -th segment of the roll gap of the k -th stand, unit: MPa, ΔX k is the length of the discrete segment of the roll gap of the k -th stand, unit: mm, h k (i) is the strip thickness of the i -th segment of the roll gap of the k -th stand, unit: mm, Δh k (i) = h k (i + 1)-h k (i), h 1k is the rolled piece exit thickness of the k -th stand, unit: mm, f k is the forward slip value of the k -th stand.
[0017] Furthermore, in S400, calculate the rolled piece inlet thickness h 0k and the rolled piece exit thickness h 1k , specifically: when k = 1, h 0k = H, h 1k =(1 - η k )H; when 2 ≤ k ≤ Q - 1, h 0k = h 1(k-1) , h 1k =(1 - η k )h 0k ; when k = Q, h0k = h 1(k-1) , h 1k = h; The subscript k represents the stand number, 1 ≤ k ≤ Q, and η k is the reduction ratio of the k-th stand.
[0018] Further, in S500, calculate the rolling force energy parameters of each stand. The specific steps are as follows:
[0019] S501. Repeatedly iterate the stress differential equation and roll gap thickness equation in the roll gap deformation zone to calculate the unit pressure distribution, friction stress distribution, and roll gap thickness distribution in the roll gap deformation zone;
[0020] S502. Calculate the rolling pressure P k (unit: KN), transmission torque M k (unit: KN×m), and forward slip value f k ;
[0021] S503. Calculate the roll speed v k (unit: m / min) and main motor power N k (unit: KW).
[0022] Further, the specific steps of S501 are as follows:
[0023] S5011. Set the initial roll profile curve and determine the entrance position of the rolled piece;
[0024] S5012. Calculate the unit pressure and friction stress of each section in the back slip zone from the entrance to the exit
[0025] S5013. Calculate the unit pressure and friction stress of each section in the forward slip zone from the exit to the entrance;
[0026] S5014. Determine the unit pressure and friction stress of each section in the roll gap deformation zone;
[0027] S5015. Calculate the roll gap thickness distribution from the unit pressure distribution;
[0028] S5016. Judge whether the roll gap thickness distributions obtained from the previous two calculations converge: If they converge, end the calculation; if not, go to step S5012 for the next round of iterative calculation until the roll gap thickness distribution converges.
[0029] Further, in S502, calculate the rolling pressure P k (unit: KN), transmission torque M k (unit: KN×m), and forward slip value f k , and the specific calculation formulas are as follows:
[0030]
[0031]
[0032] In the formula, p k (i) is the unit pressure of the i-th segment of the roll gap of the k-th stand, in MPa, and Δh k (i) is the thickness difference between the (i + 1)-th segment and the i-th segment of the roll gap of the k-th stand, in mm, and Δh k (i) = h k (i + 1) - h k (i), and x k (i) is the abscissa of the i-th segment of the roll gap of the k-th stand, in mm, and m wb is the rolling friction force arm between the work roll and the backup roll, in mm, Among them, E wk is the elastic modulus of the work roll, in MPa, and E bk is the elastic modulus of the backup roll, in MPa, and L wb is the contact length between the work roll and the backup roll, in mm. When B wk ≤B bk , then L wb = B wk , when B wk >B bk , then L wb = B bk ; ρ bk is the friction circle radius of the backup roll bearing, in mm, Among them, μ′ k is the rolling friction coefficient of the backup roll bearing; h k (r) is the roll gap thickness of the corresponding segment of the neutral plane of the roll gap of the k-th stand (the r-th segment of the roll gap of the k-th stand), in mm, and Δh k (r) = h k (r + 1) - h k (r).
[0033] Furthermore, in S503, calculate the roll speed v k (unit: m / min) and the main motor power N k (unit: KW). The specific steps are as follows:
[0034] S5031. Calculate the second flow rate value V k_max with the maximum roll speed v k set for each stand. The calculation formula is: V k = h 1k v k_max (1 + f k );
[0035] S5032. Find the minimum value V Q of the second flow rate values V1 to V min, and calculate the roll speed v′ of each stand according to the second flow rate theorem by V min Calculate the roll speed v′ of each stand k , and the calculation formula is:
[0036] S5033. Calculate the main motor power N′ of each stand k , and the main motor power N′ k and the ratio φ of the rated power N of the main motor of this stand k_max is k , and the calculation formula is: Among them, M k is the transmission torque, and D wk is the working roll body diameter;
[0037] S5034. Find the maximum value φ of φ1~φ Q ; max ;
[0038] S5035. Judge whether φ max is greater than 1: If φ max > 1, then limit the roll speed of each stand by φ max , and the roll speed after limiting is the calculated roll speed of each stand, that is When φ max ≤1, then v k = v′ k ;
[0039] S5036. Calculate the main motor power N of each stand k , and the calculation formula is:
[0040] Furthermore, in S300, the reduction ratio of each stand is initially set by the optimization algorithm and the reduction ratio of each stand is adjusted by the optimization algorithm. The optimization algorithm adopts a genetic algorithm or a particle swarm algorithm.
[0041] Furthermore, in S600, judge whether the minimum roll gap friction work optimization target and the constraint conditions are simultaneously satisfied. The constraint conditions are specifically that all stands simultaneously satisfy the following inequalities:
[0042] η k_min ≤η k ≤η k_max , v k ≤v k_max , P k ≤P k_max , M k ≤M k_max , N k ≤N k_max , where the subscript k represents the stand number, 1≤k≤Q; η k_max is the maximum reduction ratio of the k-th stand, ηk_min is the minimum reduction ratio of the k-th stand, v k_max is the maximum roll speed of the k-th stand, P k_max is the maximum rolling pressure of the k-th stand, M k_max is the maximum transmission torque of the k-th stand, N k_max is the rated power of the main motor of the k-th stand.
[0043] The beneficial effects of the above technical solutions provided by the embodiments of the present invention at least include:
[0044] A method for obtaining the reduction ratio of a continuous rolling mill unit that can reduce roll wear disclosed by the present invention establishes a reduction ratio distribution model of the continuous rolling mill unit with the minimum roll gap friction work as the optimization goal through theoretical analysis. In the calculation process, an optimization algorithm is used to continuously obtain a more optimal reduction ratio distribution, and according to the given process parameters and equipment parameters, the rolling force and energy parameters of each stand under the corresponding reduction ratio distribution are repeatedly calculated, including rolling pressure, transmission torque, forward slip value, roll speed, and main motor power. Finally, the optimal reduction ratio distribution that meets the optimization goal and constraint conditions is obtained.
[0045] The principle of the method disclosed by the present invention is clear and definite, the iterative calculation is stable and rapid, and it can be used for the online preset calculation of the reduction ratio distribution of the continuous rolling mill unit, avoiding the errors brought by the traditional manual experience table setting method. Since the roll wear is positively correlated with the roll gap friction work, the calculated reduction ratio distribution can make the roll gap friction work of the continuous rolling mill unit reach the lowest, and then make the total roll wear of each stand reach the minimum, thereby reducing the roll consumption in the rolling production process, reducing the roll changing frequency, and increasing the rolling production volume in the single roll period.
[0046] The technical solutions of this embodiment will be further described in detail below through the drawings and embodiments. Description of the Drawings
[0047] The drawings are used to provide a further understanding of this embodiment, and constitute a part of the specification. They are used together with this embodiment to explain the present invention, and do not constitute a limitation to this embodiment. In the drawings:
[0048] Figure 1 is the calculation flow chart of a method for obtaining the reduction ratio of a continuous rolling mill unit that can reduce roll wear in Embodiment 1;
[0049] Figure 2 is the calculation flow chart of the rolling force and energy parameters of the k-th stand in Embodiment 1;
[0050] Figure 3 is the calculation flow chart of the repeated iteration of the stress differential equation and the roll gap thickness equation in the roll gap deformation zone in Embodiment 1;
[0051] Figure 4 In Example 1, it is the calculation flow chart of the roll speed and the main motor power;
[0052] Figure 5 In Example 2, it is the roll gap thickness distribution calculated under the reduction ratio distribution conditions of each stand given by the traditional manual experience table setting method;
[0053] Figure 6 In Example 2, it is the roll gap friction stress distribution calculated under the reduction ratio distribution conditions of each stand given by the traditional manual experience table setting method;
[0054] Figure 7 In Example 2, it is the curve of the fitness value changing with the number of evolutionary generations during the iterative calculation using the genetic algorithm;
[0055] Figure 8 In Example 2, it is the roll gap thickness distribution of each stand calculated by iterative calculation using the genetic algorithm;
[0056] Figure 9 In Example 2, it is the roll gap friction stress distribution of each stand calculated by iterative calculation using the genetic algorithm;
[0057] Figure 10 In Example 2, it is the curve of the fitness value changing with the number of evolutionary generations during the iterative calculation using the particle swarm optimization algorithm.
[0058] Figure 11 In Example 2, it is the roll gap thickness distribution of each stand calculated by iterative calculation using the particle swarm optimization algorithm;
[0059] Figure 12 In Example 2, it is the roll gap friction stress distribution of each stand calculated by iterative calculation using the particle swarm optimization algorithm. Detailed implementation manners
[0060] Hereinafter, the exemplary embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be completely conveyed to those skilled in the art.
[0061] In order to solve the problems existing in the prior art, this embodiment provides a method for obtaining the reduction ratio of a continuous rolling mill unit that can reduce roll wear.
[0062] Example 1
[0063] A method for obtaining the reduction ratio of a continuous rolling mill unit that can reduce roll wear, such as Figure 1 , includes:
[0064] S100. Input process parameters and continuous rolling mill equipment parameters; specifically, in this embodiment S100, the process parameters include the incoming material thickness H (unit: mm), the finished product thickness h (unit: mm), the width B of the rolled piece s (unit: mm), the number of stands Q, and the rolled piece deformation resistance data. The continuous rolling mill equipment parameters include the working roll body diameter D wk (unit: mm), the working roll neck diameter D' wk (unit: mm), the working roll body width B wk (unit: mm), the backup roll body diameter D bk (unit: mm), the backup roll neck diameter D' bk (unit: mm), and the backup roll body width B bk (unit: mm), where the subscript k represents the stand number, and 1 ≤ k ≤ Q.
[0065] S200. Establish the minimum roll gap friction work optimization objective and constraints; in this embodiment S200, the objective function of the minimum roll gap friction work optimization objective is:
[0066]
[0067] In the formula, n k is the number of discrete segments of the roll gap of the k-th stand, t k (i) is the friction stress of the i-th segment of the roll gap of the k-th stand, unit: MPa, ΔX k is the length of the discrete segment of the roll gap of the k-th stand, unit: mm, h k (i) is the strip thickness of the i-th segment of the roll gap of the k-th stand, unit: mm, Δh k (i) = h k (i + 1) - h k (i), h 1k is the rolled piece outlet thickness of the k-th stand, unit: mm, f k is the forward slip value of the k-th stand.
[0068] The constraints include the maximum reduction ratio η k_max of each stand, the minimum reduction ratio η k_min , the maximum roll speed v k_max (unit: m / min), the maximum rolling pressure P k_max (unit: KN), the maximum transmission torque M k_max (unit: KN×m), and the rated power N k_max (unit: KW) of the main motor.
[0069] S300. Use the optimization algorithm to initially set the reduction ratios η1, η2... η from the 1st stand to the Q - 1st stand Q-1; In the present embodiment S300, the reduction ratios of each rolling mill stand are initially set by an optimization algorithm and the reduction ratios of each rolling mill stand are adjusted by the optimization algorithm. Preferably, a genetic algorithm or a particle swarm algorithm is adopted; the principles of the genetic algorithm and the particle swarm algorithm belong to the publicly known knowledge in the industry and will not be elaborated here.
[0070] S400. Calculate the entrance thickness and the exit thickness of the rolled piece for each rolling mill stand; specifically, in S400, calculate the entrance thickness h 0k and the exit thickness h 1k of the rolled piece for each rolling mill stand. Specifically: when k = 1, h 0k = H, h 1k = (1 - η k )H; when 2 ≤ k ≤ Q - 1, h 0k = h 1(k-1) , h 1k = (1 - η k )h 0k ; when k = Q, h 0k = h 1(k-1) , h 1k = h; the subscript k represents the rolling mill stand number, 1 ≤ k ≤ Q, and η k is the reduction ratio of the k-th rolling mill stand.
[0071] S500. Calculate the rolling force and energy parameters of each rolling mill stand. Among them, the rolling force and energy parameters of each rolling mill stand include the rolling pressure, transmission torque, forward slip value, roll speed, and main motor power of each rolling mill stand;
[0072] Specifically, taking the calculation of the k-th rolling mill stand as an example for illustration, as Figure 2 shown, the specific steps are as follows:
[0073] S501. Repeatedly iterate by the stress differential equation and the roll gap thickness equation in the roll gap deformation zone to calculate the unit pressure distribution, friction stress distribution, and roll gap thickness distribution in the roll gap deformation zone;
[0074] S502. Calculate the rolling pressure P k (unit: KN), the transmission torque M k (unit: KN×m), and the forward slip value f k ;
[0075] S503. Calculate the roll speed v k (unit: m / min) and the main motor power N k (unit: KW).
[0076] Among them, as Figure 3 shown, S501 is specifically:
[0077] S5011. Set the initial roll profile curve and determine the entrance position of the rolled piece;
[0078] Assume that the roll is not deformed and is circular arc-shaped. At this time, the distribution of the roll flattening amount is δ(x) = 0. Discretize the deformation zone: Divide the deformation zone into n segments along the rolling direction. The roll gap thickness model equation under the circular arc-shaped roll profile is where x k (i) is the abscissa of the i-th segment, h k (i) is the thickness of the rolled piece in the i-th segment, x k (n) = 0, h k (n) = h 1k , h k (1) = h 0k . Therefore The length of the discrete segment x k (i) = x k (1)+(i - 1)ΔX, Δh k (i) = h k (i + 1)-h k (i).
[0079] S5012. Calculate the unit pressure and frictional stress of each segment in the back slip zone from the entrance to the exit; specifically:
[0080] Use the back slip zone formula to calculate from the entrance to the exit and judge the partition situation between sliding friction and sticking friction:
[0081] Calculate the unit pressure p k (1) b _sli of the entrance segment (the first segment) under the condition of sliding friction as:
[0082]
[0083] In the formula, K k (1) is the deformation resistance of the rolled piece in the first segment of the roll gap, with the unit of MPa, μ k is the roll gap friction coefficient of the k-th stand;
[0084] Then use the Aitken iterative method to solve p k (1) b _sli;
[0085] Judge μ at the entrance segment k p k (1) b _sli and size, and divide it into two cases:
[0086] (i) If Then it indicates that the entrance segment is sliding friction, and the unit pressure p k (1) b = p k (1)b _sli. Calculate the unit pressure of the second section, the third section... the nth section in turn using the stress differential equation in the backward slip zone under sliding friction conditions, and judge μ in each section k p(i) b _sli(1 ≤ i ≤ n) and magnitude; specifically:
[0087] The unit pressure of the (i + 1)th section in the backward slip zone under sliding friction conditions is:
[0088] The friction stress of the ith section in the backward slip zone under sliding friction conditions is: t k (i) b _sli = μ k p k (i) b _sli.
[0089] There are two situations in the calculation process:
[0090] 1) If it satisfies from the entrance section (the first section) to the exit section (the nth section) (1 ≤ i ≤ n), it means that the calculation from the entrance to the exit is sliding friction when using the stress differential equation in the backward slip zone under sliding friction conditions; at this time, the unit pressures of each section calculated using the backward slip zone formula are: p k (1) b = p k (1) b _sli, p k (2) b = p k (2) b _sli... p k (n) b = p k (n) b _sli;
[0091] 2) If at the mth (1 < m ≤ n) section there is: It means that from the mth section to the exit is sticking friction; switch to using the stress differential equation in the backward slip zone under sticking friction conditions to calculate the unit pressures of the mth section, the (m + 1)th section... the nth section in turn; specifically:
[0092] The unit pressure of the (i + 1)th section in the backward slip zone under sticking friction conditions is:
[0093]
[0094] The friction stress of the ith section in the backward slip zone under sticking friction conditions is:
[0095] At this time, the unit pressures of each section calculated using the back-sliding zone formula are: p k (1) b = p k (1) b _sli, p k (2) b = p k (2) b _sli…p k (m - 1) b = p k (m - 1) b _sli, p k (m) b = p k (m) b _sti, p k (m + 1) b = p k (m + 1) b _sti…p k (n) b = p k (n) b _sti;
[0096] (ii) If then it indicates that the entrance section is adhesive friction, and the entire section from the entrance to the exit is adhesive friction; the unit pressure of the entrance section ; use the stress differential equation of the back-sliding zone under the condition of adhesive friction to calculate the unit pressures of the 2nd section, 3rd section... nth section in sequence; the unit pressures of each section calculated using the back-sliding zone formula are p k (1) b = p k (1) b _sti, p k (2) b = p k (2) b _sti……p k (n) b = p k (n) b _sti.
[0097] S5013. Calculate the unit pressures and frictional stresses of each section in the forward-sliding zone from the exit to the entrance; similar to the calculation method of the back-sliding zone, specifically:
[0098] Use the forward-sliding zone formula to calculate from the exit to the entrance and judge the zoning situation of sliding friction and adhesive friction.
[0099] 1. Calculate the unit pressure p k (n) f _sli of the exit section under the condition of sliding friction as:
[0100] Solve for p using the Aitken iterative method k (n) f _sli;
[0101] 2. Judge μ at the exit section k p k (n) f _sli and the magnitudes, and divide into two cases:
[0102] (i) If it indicates that the exit section is under sliding friction, and the unit pressure p k (n) f = p k (n) f _sli; Use the stress differential equation in the forward slip zone under sliding friction conditions to calculate the unit pressures of the (n - 1)th section, (n - 2)th section,... in sequence, and judge μ at each section k p k (i) f _sli (1 ≤ i ≤ n) and the magnitudes. Specifically:
[0103] The unit pressure of the ith section in the forward slip zone under sliding friction conditions is:
[0104] Solve for p k (i) f _sli using the Aitken iterative method.
[0105] The friction stress of the ith section in the forward slip zone under sliding friction conditions is: t k (i) f _sli = -μ k p k (i) f _sli, and the negative sign indicates that the direction of the friction stress in the forward slip zone is towards the entrance side (opposite to the rolling direction).
[0106] Among them, there are two cases during the calculation process:
[0107] 1) If it is satisfied from the exit section to the entrance section it indicates that when calculating using the stress differential equation in the forward slip zone under sliding friction conditions, it is sliding friction from the exit to the entrance. At this time, the unit pressures of each section calculated using the forward slip zone formula are: p k (1) f = p k (1) f _sli, p k (2) f = pk (2) f _sli…p k (n) f =p k (n) f _sli;
[0108] 2) If at the s-th segment (1 < s ≤ n), there is: It indicates that from the s-th segment to the entrance, it is all sticking friction; then use the stress differential equation in the forward slip zone under sticking friction conditions to calculate the unit pressure of the s-th segment, the (s - 1)-th segment... the 1st segment in sequence; specifically:
[0109] The unit pressure of the i-th segment in the backward slip zone under sticking friction conditions is:
[0110]
[0111] The friction stress of the i-th segment in the backward slip zone under sticking friction conditions is:
[0112] At this time, the unit pressure of each segment calculated using the forward slip zone formula is: p k (1) f =p k (1) f _sti、p k (2) f =p k (2) f _sti…p k (s) f =p k (s) f _sti、p k (s + 1) f =p k (s + 1) f _sli…p k (n) f =p k (n) f _sli;
[0113] (ii) If It indicates that the exit segment is sticking friction, and from the exit segment to the entrance segment is all sticking friction; the unit pressure of the exit segment Use the stress differential equation in the backward slip zone under sticking friction conditions to calculate the unit pressure of the (n - 1)-th segment, the (n - 2)-th segment... the 1st segment in sequence;
[0114] At this time, the unit pressure of each segment calculated using the forward slip zone formula is p k (1) f =p k (1) f _sti、pk (2) f = p k (2) f _sti……p k (n) f = p k (n) f _sti。
[0115] S5014. Determine the unit pressure and frictional stress of each section in the roll gap deformation zone;
[0116] Compare the two sets of unit pressures p k (1) f 、p k (2) f ……p k (n) f and p k (1) b 、p k (2) b ……p k (n) b ,find the section with the smallest difference (assumed to be the r-th section), then this section is the boundary section between the forward slip zone and the backward slip zone (i.e., the section corresponding to the neutral plane), x k (r) = x k (1)+(r - 1)ΔX, and retain p k (1) b 、p k (2) b ……、p k (r - 1) b 、p k (r) b or p k (r) f 、p k (r + 1) f ……p k (n) f ; So far, the unit pressure distribution under the specified roll profile has been calculated, that is, p k (1) = p k (1) b 、p k (2) = p k (2) b 、……、p k (r - 1) = p k (r - 1) b 、p k (r) = p k (r) b or p k (r) = p k (r)f , p k (r + 1) = p k (r + 1) f ……p k (n) = p k (n) f , and the friction stress distribution t k (1) = t k (1) b , t k (2) = t k (2) b ……, t k (r - 1) = t k (r - 1) b , t k (r) = t k (r) b or t k (r) = t k (r) f , t k (r + 1) = t k (r + 1) f ……t k (n) = t k (n) f ;
[0117] S5015. Calculate the roll gap thickness distribution from the unit pressure distribution;
[0118] Calculate the roll gap thickness h using the unit pressure distribution k (i); However, to ensure convergence, a smoothing coefficient e needs to be introduced here to make the unit pressures of each section calculated in the previous and next 2 iterations change smoothly;
[0119] That is, p k m+1 (i) = ep k (i) + (1 - e)p k m (i), 0 < e < 1, p k (i) - The unit pressure of the i-th section of the roll gap under the specified roll profile calculated; p k m (i) - The unit pressure of the i-th section of the roll gap used in the m-th iteration; p k m+1 (i) - The unit pressure of the i-th section of the roll gap used in the (m + 1)-th iteration;
[0120] Calculate the elastic flattening deformation amount δ(x of the roll using the smoothed unit pressure distribution p k m+1 (i) k(j)), the elastic flattening of the roll at the abscissa x is calculated by the method of cumulative summation k at (j) j = 1, 2, 3…n, s i is the unit pressure p k m+1 (i) corresponding abscissa, unit mm; E wk is the elastic modulus of the working roll of the k-th stand, unit MPa; v wk is the Poisson's ratio of the working roll of the k-th stand;
[0121] Then the distribution of the deformed roll profile curve is obtained as:
[0122]
[0123] The roll gap thickness distribution is:
[0124] In the formula, y(x k (j)) min - the ordinate corresponding to the lowest point of the deformed roll profile curve, unit mm;
[0125] S5016. Judge whether the roll gap thickness distributions obtained from the previous and current calculations converge: If they converge, end the calculation; if they do not converge, go to step S5012 for the next round of iterative calculation until the roll gap thickness distribution converges;
[0126] Corresponding to the unit pressure distribution, smooth the roll gap thickness, that is, h k m+1 (j) = eh k (j)+(1 - e)h k m (j), in the formula, h k (j) - the thickness of the j-th section of the roll gap calculated; h k m (j) - the thickness of the j-th section of the roll gap used in the m-th iteration; h k m +1 (j) - the thickness of the j-th section of the roll gap used in the (m + 1)-th iteration.
[0127] Using the new roll gap thickness distribution (h k m+1 (j)) to re-solve the unit pressure distribution and frictional stress distribution under the roll profile in the same way as above, and iterate repeatedly until convergence; the convergence condition is: the absolute value of the difference in the roll gap thickness of each corresponding section calculated in the previous and current times is less than the precision value, that is, |h k (j) - h k m (j)| ≤ ε × h k(j), ε-convergence precision coefficient.
[0128] After iterative convergence, all the unit pressure distributions p that meet the conditions have been calculated so far. k (1), p k (2), p k (3), … p k (n), frictional stress distribution t k (1), t k (2), t k (3), … t k (n) and roll gap thickness distribution h k (1), h k (2), h k (3), … h k (n).
[0129] In S502 of this embodiment, the rolling pressure P k (unit: KN), driving torque M k (unit: KN×m) and forward slip value f k , and the specific calculation formula is:
[0130]
[0131]
[0132] In the formula, p k (i) is the unit pressure of the i-th section of the roll gap of the k-th stand, unit: MPa, Δh k (i) is the thickness difference between the (i + 1)-th section and the i-th section of the roll gap of the k-th stand, unit: mm, Δh k (i) = h k (i + 1) - h k (i), x k (i) is the abscissa of the i-th section of the roll gap of the k-th stand, unit: mm, m wb is the rolling friction force arm between the work roll and the backup roll, unit: mm, Among them, E wk is the elastic modulus of the work roll, unit: MPa, E bk is the elastic modulus of the backup roll, unit: MPa, L wb is the contact length between the work roll and the backup roll, unit: mm, when B wk ≤B bk When, L wb = B wk When B wk > B bk When, L wb = B bk ; ρ bk is the friction circle radius of the backup roll bearing, unit: mm, Among them, μ′ k is the rolling friction coefficient of the backup roll bearing; h k (r) is the roll gap thickness of the corresponding section of the neutral plane of the roll gap of the k-th stand (the r-th section of the roll gap of the k-th stand), in mm, and Δh k (r) = h k (r + 1) - h k (r).
[0133] In S503 of this embodiment, the roll speed v k (unit: m / min) and the main motor power N k (unit: KW) are calculated. As Figure 4 shown, the specific steps are as follows:
[0134] S5031. Calculate the second flow rate value V k_max with the maximum roll speed v k set for each stand. The calculation formula is: V k = h 1k v k_max (1 + f k );
[0135] S5032. Find the minimum value V Q of the second flow rate values V1 to V min of each stand, and calculate the roll speed v′ min of each stand according to the second flow rate theorem. The calculation formula is: k
[0136] S5033. Calculate the main motor power N′ k of each stand, as well as the ratio φ k of the main motor power N′ k_max to the rated power N k of the main motor of this stand. The calculation formula is:
[0137] S5034. Find the maximum value φ Q of φ1 to φ max ;
[0138] S5035. Judge whether φ max is greater than 1: If φ max > 1, then limit the roll speed of each stand by φ max . The limited roll speed is the calculated roll speed of each stand, that is When φ max ≤ 1, then v k = v′ k ;
[0139] S5036. Calculate the main motor power N of each stand k , and the calculation formula is:
[0140] So far, the rolling force and energy parameters of the k-th stand have been calculated, including the rolling pressure P k (unit: KN), the driving torque M k (unit: KN×m), the forward slip value f k , the roll speed v k (unit: m / min), and the main motor power N k (unit: KW). The calculation methods of the rolling force and energy parameters of other stands are similar to the above, and will not be elaborated here.
[0141] S600. Judge whether the minimum roll gap friction work optimization goal and the constraint conditions are simultaneously satisfied: If not, adjust the reduction ratio values of each stand by the optimization algorithm, and then transfer to S400 for recalculation. If satisfied, the calculation ends.
[0142] Specifically, in S600, judge whether the minimum roll gap friction work optimization goal and the constraint conditions are simultaneously satisfied. The constraint conditions are specifically that all stands simultaneously satisfy the following inequalities:
[0143] η k_min ≤η k ≤η k_max , v k ≤v k_max , P k ≤P k_max , M k ≤M k_max , N k ≤N k_max , where the subscript k represents the stand number, 1≤k≤Q; η k_max is the maximum reduction ratio of the k-th stand, η k_min is the minimum reduction ratio of the k-th stand, v k_max is the maximum roll speed of the k-th stand, P k_max is the maximum rolling pressure of the k-th stand, M k_max is the maximum driving torque of the k-th stand, N k_max is the rated power of the main motor of the k-th stand.
[0144] A method for obtaining the reduction rate of a continuous rolling mill unit that can reduce roll wear. Through theoretical analysis, a reduction rate distribution model of the continuous rolling mill unit with the minimum roll gap friction work as the optimization target is established. In the calculation process, an optimization algorithm is used to continuously obtain a better reduction rate distribution, and according to the given process parameters and equipment parameters, the rolling force and energy parameters of each stand under the corresponding reduction rate distribution are repeatedly calculated, including rolling pressure, transmission torque, forward slip value, roll speed, and main motor power. Finally, the optimal reduction rate distribution that meets the optimization target and constraint conditions is obtained.
[0145] The principle of the method disclosed in this embodiment is clear and definite, and the iterative calculation is stable and rapid. It can be used for the online preset calculation of the reduction rate distribution of the continuous rolling mill unit, avoiding the errors caused by the traditional manual experience table setting method. The calculated reduction rate distribution can make the roll gap friction work of the continuous rolling mill unit reach the lowest, and further make the total roll wear of each stand reach the minimum, so as to reduce the roll consumption in the rolling production process, reduce the roll change frequency, and increase the rolling production volume in the single-roll period.
[0146] Embodiment 2
[0147] For the sake of easy understanding, the following further illustrates with Embodiment 2. In this embodiment, the process parameters include: the incoming material thickness H = 17 mm, the finished product thickness H = 2 mm, the width of the rolled piece B s = 1600 mm, and the number of stands Q = 5. The equipment parameters are shown in Table 1. The constraint condition parameters are shown in Table 2.
[0148] Table 1 shows the equipment parameters of Embodiment 2
[0149]
[0150] Table 2 shows the constraint condition parameters of Embodiment 2
[0151]
[0152] Other parameters include: the number of segments n = 500 divided along the rolling direction in the roll gap deformation zone, the convergence precision coefficient ε of the roll gap thickness distribution = 0.001, the smoothing coefficient e = 0.3, the density of the rolled piece ρ = 7800 kg / m 3 , the roll gap friction coefficients of each stand μ1 = μ2 = μ3 = μ4 = μ5 = 0.3, and the elastic modulus E of the working rolls of each stand w1 = E w2 = E w3 = E w4 = E w5 = 206000 MPa, and the elastic modulus E of the backup rolls of each stand b1 = E b2 = E b3 = E b4 = Eb5 = 206000 MPa, the Poisson's ratio v of the work rolls of each stand w1 = v w2 = v w3 = v w4 = v w5 = 0.3, the rolling friction coefficients of the support roll bearings of each stand are μ′1 = μ′2 = μ′3 = μ′4 = μ′5 = 0.002.
[0153] As shown in Table 3, the data of the deformation resistance of the rolled piece are given in the form of a data table of the change of the deformation resistance of the rolled piece with the reduction ratio.
[0154] Table 3 is the data of the deformation resistance of the rolled piece
[0155]
[0156] The deformation resistance of the rolled piece at each position of the roll gap of each stand is calculated by the linear interpolation method:
[0157] Taking the 3rd stand as an example, assuming that the calculated entrance thickness of the rolled piece of the 3rd stand is 5 mm and the exit thickness is 3.2 mm, then the total reduction ratio of the entrance rolled piece of this stand is The total reduction ratio of the exit rolled piece is Then, the deformation resistance of the entrance rolled piece of this stand can be calculated by the linear interpolation method as The deformation resistance of the exit rolled piece of this stand is
[0158] Furthermore, taking the i-th section (1 ≤ i ≤ 500) of the roll gap of the 3rd stand as an example, the reduction ratio per pass of this stand is Assuming that the thickness of the rolled piece h3(i) in the i-th section of the roll gap of the 3rd stand is 4 mm, then the reduction ratio of the rolled piece in the i-th section is Then, further using the linear interpolation method, the deformation resistance of the rolled piece in the i-th section of the roll gap of the 3rd stand can be calculated as:
[0159]
[0160] The deformation resistance of the rolled piece at each position of the roll gap of other stands can be calculated according to the above method and will not be elaborated here.
[0161] For comparison, Table 4 shows the reduction ratio distribution of each stand and the calculated force and energy parameters given by a traditional manual experience table setting method in a certain steel plant. The roll gap thickness distribution and friction stress distribution of each stand are respectively as Figure 5 and Figure 6 shown. The reduction ratios of each stand and the calculated roll gap friction work of each stand are shown in the 4th column and the 11th column of Table 4 respectively. The total roll gap friction work under this reduction ratio distribution can be further calculated as 0.63289 KN×m.
[0162] Table 4 Roll reduction ratio distribution of each stand given by the traditional manual experience table setting method and the calculated force and energy parameters
[0163]
[0164] Specifically, in this embodiment, the optimization algorithms respectively adopt the genetic algorithm and the particle swarm algorithm. When the genetic algorithm is used as the optimization algorithm, the principle of the genetic algorithm belongs to the publicly known knowledge in the industry and will not be elaborated here. The relevant calculation parameters of the genetic algorithm adopted in this embodiment are: the population size is 80, the crossover probability is 0.95, the mutation probability is 0.1, the selection method is roulette wheel selection, the crossover method is single-point crossover, the maximum number of evolution generations is 100, and the curve of the fitness value changing with the number of evolution generations during the iterative calculation process is as Figure 7 shown.
[0165] The roll gap thickness distribution and friction stress distribution of each stand calculated in this embodiment are respectively as Figure 8 and Figure 9 shown. The roll reduction ratio of each stand and the corresponding roll gap friction work are shown in the 4th column and the 11th column of Table 5 respectively. Further calculated, the total roll gap friction work is 0.58879 KN×m. Comparing with the data given by the traditional manual experience table setting method (Table 4), it shows that the method of this embodiment can reduce the roll gap friction work by about 7%, that is, it is equivalent to reducing the roll wear by about 7%.
[0166] Table 5 Roll reduction ratio distribution and force and energy parameters of each stand calculated in the second embodiment
[0167]
[0168] When the particle swarm algorithm is used as the optimization algorithm, the principle of the particle swarm algorithm belongs to the publicly known knowledge in the industry and will not be elaborated here. The relevant calculation parameters of the particle swarm algorithm adopted in this embodiment are: the population size is 30, the maximum number of evolution generations is 50, the inertia weight is 0.5, the acceleration coefficient of the particle's optimal position is 2, the acceleration coefficient of the global optimal position is 2, and the curve of the fitness value changing with the number of evolution generations during the iterative calculation process is as Figure 10 shown.
[0169] The roll gap thickness distribution and friction stress distribution of each stand calculated in this embodiment are respectively as Figure 11 and Figure 12 shown. The roll reduction ratio of each stand and the corresponding roll gap friction work are shown in the 4th column and the 11th column of Table 6 respectively. Further calculated, the total roll gap friction work is 0.58696 KN×m. Comparing with the data given by the traditional manual experience table setting method (Table 4), it shows that the method of this embodiment can reduce the roll gap friction work by about 7.3%, that is, it is equivalent to reducing the roll wear by about 7.3%.
[0170] Table 6 shows the roll reduction rate distribution and power and energy parameters of each stand calculated in Example 2
[0171]
[0172] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of the present disclosure. The appended method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy recited.
[0173] In the above detailed description, various features are combined in a single embodiment to simplify the present disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are expressly recited in each claim. On the contrary, as reflected in the appended claims, the present embodiments are in a state with fewer features than all the features of the disclosed single embodiment. Accordingly, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing alone as a separate preferred embodiment of the present embodiment.
[0174] Those skilled in the art should also understand that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments herein can be implemented as electronic hardware, computer software, or combinations thereof. To clearly illustrate the interchangeability of hardware and software, the above various illustrative components, blocks, modules, circuits, and steps have been generally described in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and the design constraints imposed on the overall system. Skilled artisans may implement the described functionality in a flexible manner for each particular application, but such implementation decisions should not be construed as departing from the scope of the present disclosure.
[0175] The steps of the method or algorithm described in connection with the embodiments herein may be directly embodied as hardware, a software module executed by a processor, or combinations thereof. The software module may be located in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium well known in the art. An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium. Of course, the storage medium may also be a component of the processor. The processor and the storage medium may be located in an ASIC. The ASIC may be located in a user terminal. Of course, the processor and the storage medium may also exist as discrete components in a user terminal.
[0176] For software implementation, the techniques described in this application can be implemented by modules (e.g., procedures, functions, etc.) that perform the functions described in this application. These software codes can be stored in a memory unit and executed by a processor. The memory unit can be implemented within the processor or outside the processor. In the latter case, it is communicatively coupled to the processor via various means, which are well known in the art.
[0177] The above description includes examples of one or more embodiments. Of course, it is not possible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but those of ordinary skill in the art should recognize that the various embodiments can be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications, and variations that fall within the scope of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, this term is covered in a manner similar to the term "including" as interpreted when used as a transitional word in a claim. Further, any use of the term "or" in the specification or claims of a patent is to mean "non-exclusive or".
Claims
1. A method for obtaining the reduction ratio of a continuous rolling mill unit that can reduce roll wear, characterized in that Including: S100. Input process parameters and continuous rolling mill equipment parameters; S200. Establish the optimization objective and constraint conditions of the minimum roll gap friction work; In S200, the objective function of the optimization objective of the minimum roll gap friction work is: Where n k is the number of discrete segments of the roll gap of the k-th stand, t k (i) is the friction stress of the i-th segment of the roll gap of the k-th stand, in MPa, ΔX k is the length of the discrete segment of the roll gap of the k-th stand, in mm, h k (i) is the strip thickness of the i-th segment of the roll gap of the k-th stand, in mm, Δh k (i) is the thickness difference between the (i + 1)-th segment and the i-th segment of the roll gap of the k-th stand, in mm, Δh k (i) = h k (i + 1) - h k (i), h k (i + 1) and h k (i) are the thicknesses of the (i + 1)-th segment and the i-th segment of the roll gap of the k-th stand respectively, in mm, h 1k is the thickness of the rolled piece at the exit of the k-th stand, in mm, f k is the forward slip value of the k-th stand; S300. Initially set the reduction ratios η1, η2, …, η of the first stand to the (Q - 1)-th stand by using an optimization algorithm Q-1 ; S400. Calculate the entrance thickness and exit thickness of the rolled piece for each stand; S500. Calculate the rolling force and energy parameters for each stand. Among them, the rolling force and energy parameters for each stand include the rolling pressure, transmission torque, forward slip value, roll speed, and main motor power for each stand; S600. Determine whether the optimization objective and constraint conditions of the minimum roll gap friction work are simultaneously satisfied: If not, adjust the reduction ratio values of each stand by the optimization algorithm, and then transfer to S400 for recalculation. If satisfied, the calculation ends.
2. The method for obtaining the reduction ratio of a continuous rolling mill unit capable of reducing roll wear according to claim 1, wherein In S100, the process parameters include the incoming material thickness H, unit: mm, the finished product thickness h, unit: mm, the width B of the rolled piece s , unit: mm, the number Q of stands, and the data of the deformation resistance of the rolled piece. The equipment parameters of the tandem mill include the working roll body diameter D wk of each stand, unit: mm, the working roll neck diameter D′ wk , unit: mm, the working roll body width B wk , unit: mm, the backup roll body diameter D bk , unit: mm, the backup roll neck diameter D′ bk , unit: mm, and the backup roll body width B bk , unit: mm, where the subscript k represents the stand number, 1 ≤ k ≤ Q.
3. A method for obtaining the reduction ratio of a continuous rolling mill unit capable of reducing roll wear according to claim 2, characterized in that, In S400, calculate the entrance thickness h of the rolled piece for each stand 0k and the exit thickness h 1k of the rolled piece. Specifically: when k = 1, h 0k = H, h 1k = (1 - η k )H; when 2 ≤ k ≤ Q - 1, h 0k = h 1(k-1) , h 1k = (1 - η k )h 0k ; when k = Q, h 0k = h 1(k-1) , h 1k = h; the subscript k represents the stand number, 1 ≤ k ≤ Q, and η k is the reduction ratio of the k-th stand.
4. The method for obtaining the reduction ratio of a continuous rolling mill unit capable of reducing roll wear according to claim 1, characterized in that, In S500, the specific steps for calculating the rolling force and energy parameters for each stand are as follows: S501. Repeatedly iterate using the stress differential equation and roll gap thickness equation in the roll gap deformation zone to calculate the unit pressure distribution, friction stress distribution, and roll gap thickness distribution in the roll gap deformation zone; S502. Calculate the rolling pressure P k , in units of KN, the driving torque M k , in units of KN×m and the forward slip value f k , the subscript k represents the stand number, 1 ≤ k ≤ Q, where Q is the number of stands; S503. Calculate the roll speed v k , in m / min, and the main motor power N k , in KW.
5. A method for obtaining the reduction ratio of a continuous rolling mill unit capable of reducing roll wear according to claim 4, characterized in that, The specific steps of S501 are as follows: S5011. Set the initial roll profile curve and determine the entrance position of the rolled piece; S5012. Calculate the unit pressure and friction stress for each section in the back slip zone from the entrance to the exit S5013. Calculate the unit pressure and friction stress for each section in the forward slip zone from the exit to the entrance; S5014. Determine the unit pressure and friction stress for each section in the roll gap deformation zone; S5015. Calculate the roll gap thickness distribution from the unit pressure distribution; S5016. Determine whether the roll gap thickness distributions obtained from the previous and current calculations converge: If they converge, end the calculation; If they do not converge, transfer to step S5012 for the next round of iterative calculation until the roll gap thickness distribution converges.
6. The method for obtaining the reduction rate of a continuous rolling mill unit capable of reducing roll wear according to claim 4, wherein In S502, calculate the rolling pressure P k , in the unit of KN, the driving torque M k , in the unit of KN×m and the forward slip value f k , the specific calculation formula is as follows: Wherein, n k is the number of discrete segments of the roll gap of the k-th stand, ΔX k is the length of the discrete segment of the roll gap of the k-th stand, with the unit of mm, p k (i) is the unit pressure of the i-th segment of the roll gap of the k-th stand, 1 ≤ i ≤ n, and n is the number of segments divided along the rolling direction in the roll gap deformation zone, with the unit of MPa, t k (i) is the frictional stress of the i-th segment of the roll gap of the k-th stand, with the unit of MPa, Δh k (i) is the thickness difference between the (i + 1)-th segment and the i-th segment of the roll gap of the k-th stand, with the unit of mm, Δh k (i) = h k (i + 1) - h k (i), h k (i + 1) and h k (i) are the thicknesses of the (i + 1)-th segment and the i-th segment of the roll gap of the k-th stand respectively, with the unit of mm, x k (i) is the abscissa of the i-th segment of the roll gap of the k-th stand, with the unit of mm, m wb is the rolling frictional force arm between the work roll and the backup roll, with the unit of mm, Wherein, E wk is the elastic modulus of the work roll, with the unit of MPa, E bk is the elastic modulus of the backup roll, with the unit of MPa, L wb is the contact length between the work roll and the backup roll, with the unit of mm. When B wk ≤ B bk , L wb = B wk . When B wk >B bk , L wb = B bk ; ρ bk is the friction circle radius of the backup roll bearing, with the unit of mm, Wherein, μ′ k is the rolling friction coefficient of the backup roll bearing, D′ bk is the diameter of the backup roll neck, with the unit of mm; Δh k (r) is the thickness difference between the (r + 1)-th segment and the r-th segment of the roll gap of the k-th stand, with the unit of mm, Δh k (r) = h k (r + 1) - h k (r), h k (r) is the roll gap thickness of the corresponding segment of the neutral plane of the roll gap of the k-th stand, and the corresponding segment of the neutral plane of the roll gap of the k-th stand is the r-th segment of the roll gap of the k-th stand, with the unit of mm, h k (r + 1) is the (r + 1)-th segment of the roll gap of the k-th stand, with the unit of mm.
7. The method for obtaining the reduction ratio of a continuous rolling mill unit capable of reducing roll wear according to claim 4, characterized in that In S503, calculate the roll speed v k , in m / min and the main motor power N k , in KW. The specific steps are as follows: S5031. Calculate the second flow rate value V based on the maximum roll speed v set for each stand k_max The calculation formula is: V k = h k × 1k v k_max × (1 + f k ), where h 1k is the thickness of the rolled piece at the outlet, in mm; S5032. Find the minimum value V of the second flow rate values V1 to V of each stand Q and, according to the second flow rate theorem, calculate the roll speed v' of each stand from V min . The calculation formula is as follows: min where h k is the thickness of the rolled piece at the outlet, in mm; h 1k is the thickness of the rolled piece at the outlet, in mm; S5033. Calculate the main motor power N of each stand k ′, and the ratio φ of the main motor power N k ′ to the rated power N of the main motor of this stand k_max is calculated by the formula: k The calculation formula is: where M k is the driving torque, and D wk is the diameter of the working roll body; S5034. Find the maximum value φ of φ1 to φ Q ; max ; S5035. Determine φ max Whether it is greater than 1: If φ max > 1, then limit the roll speed of each stand with φ max The limited roll speed is the calculated roll speed of each stand, that is When φ max ≤ 1, then v k = v' k ; S5036. Calculate the main motor power N of each rack k , and the calculation formula is as follows:
8. The method for obtaining the reduction ratio of a continuous rolling mill unit capable of reducing roll wear according to claim 1, characterized in that, In S300, the reduction ratios of each stand are initially set by the optimization algorithm and the reduction ratios of each stand are adjusted by the optimization algorithm. The optimization algorithm uses a genetic algorithm or a particle swarm algorithm.
9. The method for obtaining the reduction ratio of a continuous rolling mill unit capable of reducing roll wear according to claim 1, characterized in that, In S600, determine whether the optimization objective and constraint conditions of the minimum roll gap friction work are simultaneously satisfied. The constraint conditions are specifically that all stands simultaneously satisfy the following inequalities: η k_min ≤ η k ≤ η k_max , v k ≤ v k_max , P k ≤ P k_max , M k ≤ M k_max , N k ≤ N k_max , where the subscript k represents the stand number, 1 ≤ k ≤ Q, η k_max is the maximum reduction ratio of the k-th stand, η k_min is the minimum reduction ratio of the k-th stand, v k_max is the maximum roll speed of the k-th stand, P k_max is the maximum rolling pressure of the k-th stand, M k_max is the maximum transmission torque of the k-th stand, N k_max is the rated power of the main motor of the k-th stand.